The thermo-mechanical treatment, called "education", creates a memory effect in two directions in a memory alloy. This treatment allows memorization of a certain shape at low temperatures. This shape is exhibited by the alloy in its martensitic phase.
Obtaining this bidirectional deformation effect is essential to many industrial applications. To "educate" a part made of a memory alloy, a constant displacement or constant force is imposed on the part at certain temperatures, called the high and low temperatures. A basic cycle is then performed consisting of maintaining a high temperature associated with a displacement or a force, then changing to a low temperature that is also associated with a displacement or a force. The memory materials are educated in a rather empirical fashion so that it often takes tens or thousands of cycles to educate a part. In addition, the education conditions must be very precise to ensure reproducibility of the characteristics from one part to the next.